The natural medium for grass plant growth. Well-structured soil has sufficient channels (pore space) throughout. This allows for movement of nutrients, air and water as well as helping a pitch drain after rainfall.
There are different soil types, at a recreational level indigenous soil type will be based on natural geography in your area. However different standards of pitch need different types of soil, some pitches are constructed with sand to be firmer and fast draining. Imported soils should be cost-effective, safe and support the other factors of grass growth. Silt or clay loam blends with sand are common on football pitches.
Use all year round. Often applied at the end of the season to improve surface levels and/or improve soil structure and texture.
Poor soil might contain debris, have an unsuitable soil pH or have low nutrient levels and poor structure which will adversely affect grass plant growth.
Always work to maintain and improve soil structure.